In the past, a drum washing machine rotates a transverse-shaft type drum in an outer tank which stores water at the bottom, washings are lifted up and dropped down by baffles arranged in the drum, and the washings are thrown to an inner circumferential surface of the drum to realize washing.
In this way, in a structure of stirring the washings by the baffles, the washings are difficult to twine or rub against each other. Therefore, compared with an automatic washing machine which washes the washings through rotation of a pulsator in a washing and dewatering tank, the drum washing machine has mechanical force, acting on the washings, easy to get small, and has detergency easy to lower.
Therefore, in the drum washing machine, in order to improve the detergency, a structure that a rotating body with a protruding part on the surface is arranged at the end part of the drum and the drum and the rotating body can rotate at different rotation speeds during washing and rinsing may be adopted. In the drum washing machine, in order to properly dewater the washings, the drum and the rotating body rotate at a same rotating speed during dewatering.
A driving part that enables the drum and the rotating body to rotate can be configured in a structure that the driving part is provided with a driving motor used for the drum and a driving motor used for the rotating body, the rotation of the driving motor used for the drum is transmitted to a rotating shaft of the drum by belts so as to enable the drum to rotate, and the rotation of the driving motor used for the rotating body is transmitted to a rotating shaft of the rotating body by the belts so as to enable the rotating body to rotate (with reference to a patent literature 1).